Brake position and wear detection systems and methods

ABSTRACT

The present disclosure provides an electromechanical brake actuator system comprising an electromechanical brake actuator coupled to a derived position sensor, the derived position sensor comprising a controller, a rotation sensor, and an output drive circuit. In various embodiments, the derived position sensor may be configured to receive a first motor shaft angular velocity at a first time, receive a second motor shaft angular velocity at a second time, calculate a linear translation distance, and sum the linear translation distance and a previous ram position to obtain an actual ram position.

FIELD OF THE DISCLOSURE

The present disclosure relates to aircraft brake systems and methods,and more particularly, to systems and methods for detection of brakedisc position and wear.

BACKGROUND OF THE DISCLOSURE

Conventional aircraft wheel assemblies comprise brake stacks which stopthe aircraft in response to the compression of rotating and stationarybrake discs by either hydraulic or electromechanical actuators. Brakediscs frequently comprise carbon/carbon composite material that wearswith use, decreasing the thickness of the brake discs and the height ofthe brake stacks. Worn brake discs are replaced when wear exceeds apredetermined amount. To detect brake disc wear, aircraft wheelassemblies often utilize a wear indicator pin to determine the height ofthe brake stack. Other conventional aircraft wheel assemblies utilizelinear variable differential transformer (“LVDT”) sensors, whichelectronically measure the distance between the brake stack and thebrake housing to calculate brake disc wear. Manually inspection of wearindicator pins is subject to human error, and LVDT sensors areassociated with the addition of hardware and electronics to the aircraftwheel assembly.

SUMMARY OF THE DISCLOSURE

In various embodiments, the present disclosure provides anelectromechanical brake actuator system comprising an electromechanicalbrake actuator coupled to a derived position sensor comprising acontroller, a rotation sensor, and an output drive circuit. In variousembodiments, the controller may comprise a microcontroller. In variousembodiments, the electromechanical brake actuator may comprise a ram,and the electromechanical brake actuator system may be configured todetermine a position of the ram and/or a wear state of a brake stack.

In various embodiments, the present disclosure provides methodsdetermining a position of a ram and/or a wear state of a brake stack. Invarious embodiments, a method may comprise obtaining an actual ramposition by summing a linear translation distance and a previous ramposition. In various embodiments, a method may comprise determining thata brake stack height is less than a minimum height threshold bycomparing an actual ram position to a maximum extension position. Invarious embodiments, a method may comprise obtaining a brake stack weardistance by subtracting a worn full load position and an unworn fullload position. In various embodiments, a method may comprise obtaining arunning clearance position by subtracting a desired running clearanceand a zero torque position. In various embodiments, a method maycomprise transmitting an output signal, and/or translating a ram in alinear direction.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the present disclosure and are incorporated in, andconstitute a part of, this specification, illustrate variousembodiments, and together with the description, serve to explain theprinciples of the disclosure.

FIG. 1 illustrates a cross section view of a portion of a wheel andbrake assembly in accordance with various embodiments;

FIG. 2 illustrates a block diagram view of an electromechanical brakeactuator system in accordance with various embodiments;

FIG. 3a illustrates cross section view of a portion of anelectromechanical brake actuator system in accordance with variousembodiments;

FIG. 3b illustrates a cross section view of a portion of anelectromechanical brake actuator system in accordance with variousembodiments;

FIG. 4 illustrates a method of using an electromechanical brake actuatorsystem in accordance with various embodiments;

FIG. 5 illustrates another method of using an electromechanical brakeactuator system in accordance with various embodiments; and

FIG. 6 illustrates yet another method of using an electromechanicalbrake actuator system in accordance with various embodiments.

DETAILED DESCRIPTION

The detailed description of various embodiments herein makes referenceto the accompanying drawings, which show various embodiments by way ofillustration. While these various embodiments are described insufficient detail to enable those skilled in the art to practice thedisclosure, it should be understood that other embodiments may berealized and that logical, chemical, and mechanical changes may be madewithout departing from the spirit and scope of the disclosure. Thus, thedetailed description herein is presented for purposes of illustrationonly and not of limitation.

For example, the steps recited in any of the method or processdescriptions may be executed in any order and are not necessarilylimited to the order presented. Furthermore, any reference to singularincludes plural embodiments, and any reference to more than onecomponent or step may include a singular embodiment or step. Also, anyreference to attached, fixed, connected, or the like may includepermanent, removable, temporary, partial, full, and/or any otherpossible attachment option. Additionally, any reference to withoutcontact (or similar phrases) may also include reduced contact or minimalcontact.

For example, in the context of the present disclosure, systems andmethods may find particular use in connection with aircraft brakesystems. However, various aspects of the disclosed embodiments may beadapted for optimized performance with a variety of brake systems,including automobile brake systems and various other motor vehicle brakesystems. As such, numerous applications of the present disclosure may berealized.

With reference to FIG. 1, a portion of a wheel and brake system 10 isillustrated in accordance with various embodiments. Wheel and brakesystem 10 may comprise, for example, a brake assembly 11. In variousembodiments, brake assembly 11 may be coupled to an axle of a wheel 12.For example, brake assembly 11 consists of rotors and stators that arecompressed together by an electromechanical brake actuator 36 to reducethe speed of an aircraft. In various embodiments, brake stack 27 maycomprise components that interface with both the rotating rotors, andwith the wheel axle through torque tube 16.

Brake assembly 11 may further comprise, for example, one or moreelectromechanical brake actuators 36. For example, electromechanicalbrake actuators 36 may be configured such that in response to a commandsignal (e.g., an operator depressing a brake pedal), electromechanicalbrake actuators 36 laterally compress brake stack 27 which, in turn,resists rotation of wheel 12, thereby reducing the speed of theaircraft. Electromechanical brake actuator 36 may be coupled to orotherwise operate a motor shaft and a pressure generating device, suchas, for example, a ram 15. In response to a command signal,electromechanical brake actuator 36 causes the motor shaft to rotate.Rotational motion of the motor shaft may be transformed into linearmotion of a ball nut. Linear translation of the ball nut towards ram 15applies lateral compression force on brake stack 27.

With reference to FIG. 2, a block diagram of an electromechanical brakeactuator system 200 is illustrated in accordance with variousembodiments. Electromechanical brake actuator system 200 may comprise anelectromechanical brake actuator 210 coupled to a derived positionsensor 220. In various embodiments, derived position sensor 220 maycomprise a rotation sensor 222 and a controller 224. In variousembodiments, controller 224 may comprise a microcontroller. In variousembodiments, derived position sensor 220 may further comprise an outputdrive circuit 228 in communication with controller 224.

In various embodiments, rotation sensor 222 may comprise a resolver. Invarious embodiments, rotation sensor 222 may comprise a Hall effectsensor. In various embodiments, rotation sensor 222 may be coupled toelectromechanical brake actuator 210 and configured to detect a signalfrom which the angular velocity of the motor shaft may be calculated.

In various embodiments, controller 224 may be configured to operate as adata acquisition and digital signal processing system. For example,controller 224 may receive data from rotation sensor 222. Such data maybe processed, stored, and analyzed by controller 224. In variousembodiments, controller 224 comprises an analog to digital converter,which may be configured to receive analog data from rotation sensor 222and convert it to digital data for processing by controller 224.

In various embodiments, electromechanical brake actuator system 200 mayfurther comprise an electromechanical brake actuator controller (“EBAC”)230. After digital signal processing, data may be transmitted fromcontroller 224 to EBAC 230. In various embodiments, controller 224comprises an output drive circuit 228. For example, controller 224 maycomprise an output drive circuit which comprises an analog drivecircuit. In such embodiments, controller 224 provides data from adigital analog converter (within controller 224) to the analog drivecircuit, which may transmit the analog data to EBAC 230. The analogdrive circuit may comprise, for example, a 4 milliamp to 20 milliampdrive circuit.

In various embodiments, controller 224 comprises an output drive circuitwhich comprises a digital drive circuit. In such embodiments, controller224 provides digital data to EBAC 230. For example, the digital drivecircuit may utilize a serial communication protocol, such as, forexample, an RS232 or RS485 protocol. Although described with referenceto specific embodiments, any manner of transmitting data from controller224 to EBAC 230 is within the scope of the present disclosure.

In various embodiments, controller 224 may be capable of bidirectionalcommunication with EBAC 230. Bidirectional communication betweencontroller 224 and EBAC 230 may, for example, allow for built in testingto evaluate the health of EBAC 230 and various sensors, and/or to detectand correct error conditions, among other functions.

In various embodiments, electromechanical brake actuator system 200 mayfurther comprise a load cell 240. In various embodiments, load cell 240may be in communication with at least one of controller 224,electromechanical brake actuator 210, and electromechanical brakeactuator controller 230.

With reference to FIGS. 1, 3 a, and 3 b, an electromechanical brakeactuator 210 is illustrated in accordance with various embodiments. Invarious embodiments, electromechanical brake actuator 210 may comprise afirst end 310, a second end 311, a derived position sensor 220, and abrake actuator housing 314. In various embodiments, electromechanicalbrake actuator 210 may further comprise a motor shaft 306 oriented aboutaxis of rotation 302, which extends in a linear direction from A to A′.Rotational motion of motor shaft 306 is transformed into linear motionof a ball nut 308 along axis of rotation 302. Linear translation of ballnut 308 translates ram 15 in a linear direction along axis of rotation302. In various embodiments, ram 15 may be disposed on the second end311 of electromechanical brake actuator 210.

In various embodiments, derived position sensor 220 may be disposed onthe first end 310 of electromechanical brake actuator 210. In variousembodiments, at least a portion of derived position sensor 220 may bedisposed between brake actuator housing 314 and motor shaft 306. Invarious embodiments, at least a portion of derived position sensor 220may be disposed in electromechanical brake actuator 210, such thatderived position sensor 220 is at least partially enclosed by a housingof electromechanical brake actuator 210. In various embodiments, atleast a portion of derived position sensor 220 may be disposed onelectromechanical brake actuator 210, such that derived position sensor220 is coupled to an exterior surface of electromechanical brakeactuator 210, a housing thereof, and/or a component thereof.

FIG. 3a illustrates electromechanical brake actuator 210 in a fullyretracted state, wherein ram 15 has been translated as far as possible,or substantially as far as possible, in a linear direction towards Aalong axis of rotation 302. As used herein, a position of ram 15 shouldbe understood to be a location of ram 15 along axis of rotation 302relative to a fully retracted position 340. The location of ram 15 whenelectromechanical brake actuator 210 is in a fully retracted state maybe referred to herein as the fully retracted position 340. As usedherein, translation of ram 15 in a linear direction towards A′ may bereferred to as increasing and/or positive translation, movement, and/orposition; translation of ram 15 in a linear direction towards A may bereferred to as decreasing and/or negative translation, movement, and/orposition. Stated differently, a first position of ram 15 axially closerto A′ than a second position of ram 15 is to A′ may be described hereinas exceeding the second position of ram 15; a second position of ram 15axially closer to A than a first position of ram 15 is to A may bedescribed herein as being less than the first position of ram 15. FIG.3b illustrates electromechanical brake actuator 210 in an extendedstate, wherein ram 15 has been translated in a positive direction andthe position of ram 15 exceeds fully retracted position 340.

In various embodiments, an electromechanical brake actuator system maybe configured to determine a position of ram 15. In various embodiments,a first actual ram position may be determined by translating ram 15 afirst linear distance in a positive direction from fully retractedposition 340, such that the first actual ram position is at a firstlinear translation distance from fully retracted position 340. Invarious embodiments, the first actual ram position may be stored bycontroller 224 and/or by a component external to derived position sensor220 as a previous ram position. In various embodiments, a second actualram position may be determined by translating ram 15 a second lineardistance in a positive or a negative direction from the previous ramposition, such that the second actual ram position is at a second lineartranslation distance from fully retracted position 340. In variousembodiments, the second actual ram position may be calculated and/ordetermined by summing the first actual ram position and the secondactual ram position, and/or by summing the first linear translationdistance and the second linear translation distance. In variousembodiments, the second actual ram position may be stored by controller224 and/or by a component external to derived position sensor 220 as aprevious ram position.

In various embodiments, determination of the actual ram position from aprevious ram position may decrease occurrences of linear translation ofram 15 to the fully retracted position 340, thereby decreasing wear on,and/or increasing cycle life of, an actuator seal 320. Actuator seal 320may comprise an annular ring disposed at the second end 311 ofelectromechanical brake actuator 210 and configured to at leastpartially surround ball nut 308. Actuator seal 320 may be configured toprevent and/or minimize infiltration of water, dirt, debris,contaminants, and/or the like into brake actuator housing 314. Invarious embodiments, determination of the actual ram position from aprevious ram position may decrease linear translation of ram 15, therebydecreasing infiltration of water, dirt, debris, contaminants, and/or thelike into brake actuator housing 314.

In various embodiments, controller 224 may comprise a processorconfigured to implement various logical operations in response toexecution of instructions, for example, instructions stored on anon-transitory, tangible, computer-readable medium. As used herein, theterm “non-transitory” is to be understood to remove only propagatingtransitory signals per se from the claim scope and does not relinquishrights to all standard computer-readable media that are not onlypropagating transitory signals per se. Stated another way, the meaningof the term “non-transitory computer-readable medium” and“non-transitory computer-readable storage medium” should be construed toexclude only those types of transitory computer-readable media whichwere found in In Re Nuijten to fall outside the scope of patentablesubject matter under 35 U.S.C. §101. In various embodiments, theprocessor may be configured to implement smart algorithms to calculateand/or determine a position of ram 15 and/or a height of brake stack 27,(discussed below).

In various embodiments and with reference to FIGS. 3a, 3b , and 4, theoperations implemented in response to execution of instructions bycontroller 224 may comprise receiving a first motor shaft angularvelocity at a first time (Step 401), and receiving a second motor shaftangular velocity at a second time (Step 402). In various embodiments,the operations may further comprise calculating a linear translationdistance (Step 403) from at least one motor shaft angular velocity and aball screw lead angle factor. The ball screw lead angle factor mayrepresent the conversion of rotational motion to linear translationalmotion. In various embodiments, the operations may further comprisesumming the linear translation distance and a previous ram position toobtain an actual ram position (Step 404). In various embodiments, theoperations may further comprise transmitting an output signal (Step 407)to at least one of electromechanical brake actuator controller 230 andelectromechanical brake actuator 210. In various embodiments, the outputsignal may comprise an analog and/or digital electrical signal.

In various embodiments, an electromechanical brake actuator system maybe configured to determine a height of the brake stack. The height ofbrake stack 27 (with momentary reference to FIG. 1), referred to hereinas a brake stack height, may comprise an axial distance from a firstaxial end of brake stack 27 to a second axial end of brake stack 27.Whether the brake stack height is less than a minimum height thresholdmay be determined by comparing the actual ram position to a maximumextension threshold. In various embodiments, the maximum extensionthreshold may comprise a position of ram 15 at which, and/or greaterthan which, the brake stack height is less than a minimum heightthreshold. In various embodiments, the minimum height threshold maycomprise the brake stack height at which, and/or lower than which, brakedisc replacement is indicated. In various embodiments, the maximumextension threshold may be predetermined such that it is determined orcalculated at any time prior to comparison of the maximum extensionthreshold and the actual ram position. In various embodiments, theminimum height threshold may be predetermined such that it is determinedor calculated at any time prior to comparison of the minimum heightthreshold and the brake stack height.

In various embodiments, the operations implemented in response toexecution of instructions by controller 224 may further comprisecomparing the actual ram position to a maximum extension position (Step405). In various embodiments, the operations may further comprisedetermining that the brake stack height is less than a minimum heightthreshold, in response to the actual ram position exceeding the maximumextension position (Step 406). In various embodiments, the operationsmay further comprise transmitting an output signal (Step 407) to atleast one of electromechanical brake actuator controller 230 andelectromechanical brake actuator 210. In various embodiments, the outputsignal may communicate to the electromechanical brake actuatorcontroller 230 that the brake stack height is less than the minimumheight threshold. In various embodiments, the output signal may comprisean override command configured to override a command of theelectromechanical brake actuator controller 230. In various embodiments,the override command may comprise a command to translate the ram 15 in alinear direction and/or to a position less than the maximum extensionthreshold.

With reference again to FIGS. 3a and 3b , in various embodiments, anelectromechanical brake actuator system may be configured to determine abrake stack wear distance by subtracting a worn full load position andan unworn full load position. As used herein, a full load position maycomprise a position of ram 15, wherein ram 15 has fully translated in apositive direction towards a brake in response to a full load command.In various embodiments, the full load command may cause ram 15 to exertapproximately 50,042 newtons (11,250 pounds of force) on the brakestack. However, in various embodiments, the full load command maycomprise any desired load to be exerted on the brake stack. In variousembodiments, the full load position may be determined by a load celland/or as a result of load cell measurements, calculations, and/oroperations.

In various embodiments, the unworn full load position may comprise afull load position, wherein the brake stack has not been used and/or hasnot experienced wear. In various embodiments, the unworn full loadposition may be predetermined such that it is determined or calculatedat any time prior to subtraction of the unworn full load position andthe worn full load position. In various embodiments, the worn full loadposition may comprise a full load position, wherein the brake stack hasbeen used and/or has experienced wear. In various embodiments, theactual ram position may comprise a worn full load position.

In various embodiments, the worn full load position and the unworn fullload position may be subtracted. In various embodiments, the differencebetween the worn full load position and the unworn full load positionmay comprise the brake stack wear distance.

In various embodiments and with reference to FIGS. 3a, 3b , and 5, theoperations implemented in response to execution of instructions bycontroller 224 may comprise obtaining a worn full load position (Step501). In various embodiments, obtaining a worn full load position maycomprise any step of method 400, including receiving a first motor shaftangular velocity at a first time (Step 401), receiving a second motorshaft angular velocity at a second time (Step 402), calculating a lineartranslation distance (Step 403), and/or summing the linear translationdistance and a previous ram position to obtain an actual ram position(Step 404), wherein the actual ram position comprises a worn full loadposition. In various embodiments, the operations may further comprisesubtracting the worn full load position and an unworn full load positionto obtain a brake stack wear distance (Step 502). In variousembodiments, the operations may further comprise transmitting an outputsignal (Step 503) to at least one of electromechanical brake actuatorcontroller 230 and electromechanical brake actuator 210. In variousembodiments, the output signal may communicate to the electromechanicalbrake actuator controller 230 that the brake stack height is less thanthe minimum height threshold.

With reference again to FIGS. 3a and 3b , in various embodiments, anelectromechanical brake actuator system may be configured to determine arunning clearance position 350 by subtracting a desired runningclearance 352 and a zero torque position 360. The desired runningclearance 352 may comprise a linear distance between ram 15 and brakestack 27. In various embodiments, the desired running clearance 352 maybe between about 0.1905 centimeters (0.075 inches) and about 0.381centimeters (0.150 inches). However, the desired running clearance 352may be any distance suitable for operation of the electromechanicalbrake actuator system, and/or any distance suitable to eliminate orminimize drag while also minimizing electromechanical brake actuatorresponse time, that is, an amount of time between a command being givenby the electromechanical brake actuator and application of the commandedload by the ram.

In various embodiments, the zero torque position 360 may comprise aposition of ram 15, wherein the ram 15 is not in contact or is inminimal contact with brake stack 27 and exerts no lateral compressionforce thereon. In various embodiments, the zero torque position 360 maybe determined by a load cell and/or as a result of load cellmeasurements, calculations, and/or operations. In various embodiments,placement of the ram 15 at the zero torque position 360 may cause dragand, consequently wear, on the brake stack 27. In various embodiments,drag and/or wear may be caused by friction and/or inaccurate load cellmeasurements, calculations, and/or operations.

In various embodiments, the zero torque position 360 may be obtained bythe methods previously described herein. In various embodiments, thezero torque position 360 may be obtained and/or calculated from the wornfull load position and a compression distance, wherein the compressiondistance represents a decrease in brake stack height in response toapplication of a full load force to the brake stack 27. In variousembodiments, the zero torque position 360 may be predetermined such thatit is determined or calculated at any time prior to subtraction of thedesired running clearance 352 and the zero torque position 360. Invarious embodiments, the actual ram position may comprise a zero torqueposition 360.

In various embodiments, the zero torque position 360 and the desiredrunning clearance 352 may be subtracted. In various embodiments, thedifference between the zero torque position 360 and the desired runningclearance 352 may comprise the running clearance position 350.

In various embodiments and with reference to FIGS. 3a, 3b , and 6, theoperations implemented in response to execution of instructions bycontroller 224 may comprise obtaining a zero torque position 360 (Step601). In various embodiments, the operations may further comprisesubtracting a desired running clearance 352 and the zero torque position360 to obtain a running clearance position 350 (Step 602). In variousembodiments, the operations may further comprise transmitting an outputsignal (Step 603) to at least one of electromechanical brake actuatorcontroller 230 and electromechanical brake actuator 210. In variousembodiments, the output signal may command the electromechanical brakeactuator 210 to translate the ram 15 to the running clearance position350 (Step 604). In various embodiments, the output signal may comprisecommunicating, to the electromechanical brake actuator controller 230,at least one of the running clearance and the running clearance position350.

With reference again to FIGS. 2 and 4, a method 400 may comprisedetermining a first motor shaft angular velocity of a motor shaft at afirst time (Step 401), wherein an electromechanical brake actuator 210comprises the motor shaft and a ram 15, and is coupled to a derivedposition sensor 220 comprising a controller 224, a rotation sensor 222,and an output drive circuit 228. In various embodiments, method 400 mayfurther comprise determining a second motor shaft angular velocity at asecond time (Step 402), calculating a linear translation distance (Step403), and summing the linear translation distance and a previous ramposition to obtain an actual ram position (Step 404).

In various embodiments, method 400 may further comprise comparing theactual ram position to a maximum extension position (Step 405). Invarious embodiments, method 400 may further comprise determining that abrake stack height is less than a minimum height threshold, in responseto the actual ram position exceeding the maximum extension position(Step 406). In various embodiments, method 400 may further comprisetransmitting an output signal from the output drive circuit 228 to anelectromechanical brake actuator controller 230 (Step 407). In variousembodiments, the transmitting may comprise communicating to anelectromechanical brake actuator controller 230 the actual ram position.In various embodiments, the transmitting may comprise communicating toan electromechanical brake actuator controller 230 that the brake stackheight is less than the minimum height threshold. In variousembodiments, the transmitting may comprise overriding a command of anelectromechanical brake actuator controller 230 to prevent and/orreverse linear translation of the ram.

With reference to FIGS. 2 and 5, a method 500 may comprise obtaining aworn full load position (Step 501). In various embodiments, method 500may further comprise subtracting the worn full load position and anunworn full load position to obtain a brake stack wear distance (Step502). In various embodiments, method 500 may further comprisetransmitting an output signal from the output drive circuit to anelectromechanical brake actuator controller 230 (Step 503).

With reference to FIGS. 2 and 6, a method 600 may comprise obtaining azero torque position 360 (Step 601). In various embodiments, method 600may further comprise subtracting a desired running clearance 352 and thezero torque position 360 to obtain a running clearance position 350(Step 602). In various embodiments, method 600 may further comprisetransmitting an output signal to at least one of electromechanical brakeactuator controller 230 and electromechanical brake actuator (Step 603).In various embodiments, the transmitting may comprise commanding theelectromechanical brake actuator to translate the ram to the runningclearance position. In various embodiments, the output signal maycomprise communicating, to the electromechanical brake actuatorcontroller 230, at least one of the running clearance and the runningclearance position 350. In various embodiments, method 600 may furthercomprise translating a ram 15 to the running clearance position 350(Step 604).

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent exemplary functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the disclosure. The scope of the disclosure is accordinglyto be limited by nothing other than the appended claims, in whichreference to an element in the singular is not intended to mean “one andonly one” unless explicitly so stated, but rather “one or more.”Moreover, where a phrase similar to “at least one of A, B, or C” is usedin the claims, it is intended that the phrase be interpreted to meanthat A alone may be present in an embodiment, B alone may be present inan embodiment, C alone may be present in an embodiment, or that anycombination of the elements A, B and C may be present in a singleembodiment; for example, A and B, A and C, B and C, or A and B and C.Different cross-hatching is used throughout the figures to denotedifferent parts but not necessarily to denote the same or differentmaterials.

Devices and methods are provided herein. In the detailed descriptionherein, references to “one embodiment”, “an embodiment”, “variousembodiments”, etc., indicate that the embodiment described may include aparticular feature, structure, or characteristic, but every embodimentmay not necessarily include the particular feature, structure, orcharacteristic. Moreover, such phrases are not necessarily referring tothe same embodiment. Further, when a particular feature, structure, orcharacteristic is described in connection with an embodiment, it issubmitted that it is within the knowledge of one skilled in the art toaffect such feature, structure, or characteristic in connection withother embodiments whether or not explicitly described. After reading thedescription, it will be apparent to one skilled in the relevant art(s)how to implement the disclosure in alternative embodiments.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element herein is to be construed under theprovisions of 35 U.S.C. 112(f) unless the element is expressly recitedusing the phrase “means for.” As used herein, the terms “comprises”,“comprising”, or any other variation thereof, are intended to cover anon-exclusive inclusion, such that a process, method, article, orapparatus that comprises a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus.

1. An electromechanical brake actuator system, comprising: anelectromechanical brake actuator comprising a ram; and a derivedposition sensor, coupled to the electromechanical brake actuator andcomprising a controller, a rotation sensor, and an output drive circuit.2. The electromechanical brake actuator system of claim 1, wherein theoutput drive circuit provides a signal to an electromechanical brakeactuator controller.
 3. The electromechanical brake actuator system ofclaim 2, wherein the controller and the electromechanical brake actuatorcontroller are in bidirectional communication with each other.
 4. Theelectromechanical brake actuator system of claim 3, further comprising aload cell in communication with at least one of the controller, theelectromechanical brake actuator, and the electromechanical brakeactuator controller.
 5. The electromechanical brake actuator system ofclaim 1, further comprising a tangible, non-transitory memory configuredto communicate with the controller, the tangible, non-transitory memoryhaving instructions stored thereon that, in response to execution by thecontroller, cause the controller to perform operations.
 6. Theelectromechanical brake actuator system of claim 5, wherein theinstructions cause the controller to perform the operations comprising:receiving a first motor shaft angular velocity at a first time;receiving a second motor shaft angular velocity at a second time;calculating a linear translation distance; and summing the lineartranslation distance and a previous ram position to obtain an actual ramposition.
 7. The electromechanical brake actuator system of claim 6,wherein the instructions cause the controller to perform the operationsfurther comprising: transmitting an output signal to at least one of theelectromechanical brake actuator and an electromechanical brake actuatorcontroller.
 8. The electromechanical brake actuator system of claim 7,wherein the instructions cause the controller to perform the operationsfurther comprising: comparing the actual ram position to a maximumextension position; and determining that a brake stack height is lessthan a minimum height threshold, in response to the actual ram positionexceeding the maximum extension position.
 9. The electromechanical brakeactuator system of claim 7, wherein the actual ram position comprises aworn full load position, and wherein the instructions cause thecontroller to perform the operations further comprising: subtracting theworn full load position and an unworn full load position to obtain abrake stack wear distance.
 10. The electromechanical brake actuatorsystem of claim 7, wherein the actual ram position comprises a zerotorque position, and wherein the instructions cause the controller toperform the operations further comprising: subtracting a desired runningclearance and the zero torque position to obtain a running clearanceposition.
 11. The electromechanical brake actuator system of claim 10,wherein the instructions cause the controller to perform the operationsfurther comprising at least one of: commanding the electromechanicalbrake actuator to translate the ram to the running clearance position,and communicating, to an electromechanical brake actuator controller, atleast one of the desired running clearance and the running clearanceposition.
 12. A method of using an electromechanical brake actuatorsystem comprising: receiving, by a controller, a first motor shaftangular velocity of a motor shaft at a first time, wherein anelectromechanical brake actuator comprises the motor shaft and a ram,and is coupled to a derived position sensor comprising the controller, arotation sensor, and an output drive circuit; receiving, by thecontroller, a second motor shaft angular velocity at a second time;calculating, by the controller, a linear translation distance; summing,by the controller, the linear translation distance and a previous ramposition to obtain an actual ram position; and transmitting, by thecontroller, an output signal from the output drive circuit to anelectromechanical brake actuator controller.
 13. The method of using anelectromechanical brake actuator system of claim 12, further comprisingcomparing, by the controller, the actual ram position to a maximumextension position; and determining, by the controller, that a brakestack height is less than a minimum height threshold, in response to theactual ram position exceeding the maximum extension position.
 14. Themethod of using an electromechanical brake actuator system of claim 12,wherein the actual ram position comprises a worn full load position, andfurther comprising: subtracting, by the controller, the worn full loadposition and an unworn full load position to obtain a brake stack weardistance.
 15. The method of using an electromechanical brake actuatorsystem of claim 12, wherein the actual ram position comprises a zerotorque position, and further comprising: subtracting, by the controller,a desired running clearance and the zero torque position to obtain arunning clearance position; and translating, by the electromechanicalbrake actuator, the ram to the running clearance position.